Printing and impressing press



July 19, 1932.

J. GRUNBERG PRINTING {\ND IMPRESSING PRESS Filed Dec. so. 1929 Y 1 4 13/a. I m \ImH T 8 .6 M a w ill! W ll 2 m 1! 5 m W Ill. .1" glu l i .am JA. 1 g w a fzzVezzior: W

UNITED STATES PATENT OFFICE JOSEF GRTTNBERG, F BERLIN, GERMANY PRINTINGAND IMPRESSING- PRESS Application filed December 30, 1929, Serial No.417,531, and in Germany February 14, 1929.

This invention relates to a printing and impressing press having amovable working table or die or stamp. WVith presses of this kind it hashitherto not been possible to pre- 79 vent the arising of a one-sidedload upon the work-piece, if, owing to inaccurate guiding of the workingpiston or from other reasons, the working face of the work-piece did notlie perfectly parallel to the counter-pressing face. This proved to beof detrimental influence especially in the manufacture of stereotypematrices, in that in such a case the matrix material was not pressed onits entire surface with equal pressure onto the composition or the like.

The object of the present invention is to overcome the above-mentioneddrawback, and I attain the object in view by the provision of a movableprinting plate which is adjustable corresponding to the plane ofWorking. Owing to this provision, the arising of unequal loads upon thework-piece is effectively prevented.

The printing plate is so arranged that it can return into its normalposition when the working procedure has taken place, i. e. when it (theprinting plate) is no more in contact with the work-piece. This can bebrought about by the dead weight of said plate, as

well as by the provision of elastic pressing means.

Preferably an elastic abutment upon which the pressing plate is actingis provided. This elastic abutment forms at the same time a pressureaccumulator which becomes active when the working procedure is going on.

Said abutment can be arranged directly in the pressing plate, and thislatter is in this,

case so designed that lateral giving way of the abutment is securelyprevented.

The invention is illustrated diagrammatically and by way of example onthe accompany drawing on which Figure 1 is a vertical section through aprinting and impressing press designed according to this invention,

the press and consists, for instance, of rubber. The traverse 2 isreciprocated vertically in the frame 3 of the press, for instancehydraulically by means of a hydraulic piston (not shown), and while thusbeing moved it is guided by the vertical ledges 4 or by equivalentmembers. The abutment plate 1 which may be quadrangular is embedded in aplate 5 5 consisting of a bottom 5 and a frame or rim 5 by which membersthe plate 1 is securely held at its proper place and, especially, fromgiving way laterally. The bottom 5 constitutes at the same time theprinting plate. The plate 5 5 and the traverse 2 are connected with oneanother by vertical bolts 6 passing loosely through the traverse andbeing screwedat their lower ends into the frame or rim 5. By turning thebolts in the proper direction, the abutment 1 can be subjected to acertain preliminary tension, as may in certain cases be useful for thepurpose in v1ew.

When the traverse is moved downwardly, the bottom or printing plate 5contacts finally with the composition 8 or any substitute therefor, orwith the frame 1 enclosing the composition or the like lying on theworking table or bed 7, and as the abutment 1 is elastic the printingplate 5 adjusts itself automatically in such a way as to lie parallel tothe plane of working while the printing or impressing operation is goingon.

In the constructional form shown in F ig. 2 the elastic abutment isformed by a hollow cushion 1 which is filled with a liquid and locatedbetween the bottom face of the traverse 2 and the printing plate 5, andit is securely retained in its place by the frame orv rim 5 of the plate5, the members 5 and 5 themselves being held also in this case by bolts6, as in Fig.1.

While in Fig. 1 the traverse 2 is vertically movable, it is stationaryin Fig. 2, and there is provided below the working table or bed 7 thatsupports the composition 8, etc., a hydraulic piston 8 which isvertically movable in the cylindrical support or base 3 of the press.l/Vhen the table 7 with the frame 1' and the composition a is lifted bythe hydraulic piston 8 the printing plate 5 can also with thisconstructional form adjust itself automatically in such a way as to lieaccurately parallel to the composition.

In both constructional forms the abutments 1 and 1 constitute a pressureaccumulator which becomes active when the press remains under load forsome time, as is customary in the manufacture'of stereotype matrices andsimilar impressing work. In the presses hitherto used for this kind ofwork the work- I ing pressure falls considerably during the time inwhich the pressing or impressing work is going on, that fall being dueto the yielding of the matrix material and'of the felt plate lying onit. With my present improved press, however, the power accumulated inthe elastic abutment becomes active during the time or period stated,and the Working pressure remains practically unchanged during the timeor period.

As the printing plate is loosely suspended at the bolts 6, it assumesautomatically its proper normal position assoon as the printing orimpressing work has been finished, the

plate and the composition come out of contact, and the plate is now leftto itself.

I wish it to be understood that I do not limit myself to attaching theprinting plate I with the abutment member to the traverse,

but it may as wellbe attached to the table of the press, and while Ihave assumed in the two examples shown and describedthat the press isactuated by hydraulic power, I wish it further to be understood thatalso any other suitable driving power may be used.

I claim:

1. In a press of the class described, a bed A and a traverse element,the one movable toward and from the other, a plate on the face isimparted.

signature.

of the traverse element opposed to the bed, means detachably securingsaid plate to the traverse element, said means permitting movement ofthe plate toward and from'the face of the traverse element and anabutment element of elastic material arranged between the plate and thetraverse element and adapting the plate to adjust itself to exactparallel relationship to the bed whena working stroke 2. In a press ofthe class described, a bed and a traverse element, the one movabletoward and from the other, a plate on the face of the traverse elementopposed to the bed,

means for securing said plate to the traverse element, said meanspermitting movement of the plate toward and from the face ofvthetraverse element and elastic means acting on said plate and adapting theplate to adjust itself to exact parallel relationship to the bed when aworking stroke is imparted. In testimony whereof I have aflixed my,JOSEF GRUNBERG.

